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arXiv · 2507.17719

Continuous-wave laser source at the 148 nm nuclear transition of Th-229

Vishal Lal·Maksim V. Okhapkin·Johannes Tiedau·Niels Irwin·Valentin Petrov·Ekkehard Peik
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Abstract

A continuous-wave laser source at 148.4 nm based on second-harmonic generation in randomly quasi-phase matched strontium tetraborate, SrB4O7, is demonstrated. It provides (1.3-0.6+0.7) nW of VUV power in a single pass for an incident UV laser power of 325 mW. The laser system is developed for the resonant laser excitation of the 229Th nucleus to its low-energy isomeric state. For a frequency-stabilized laser system we expect to reach similar VUV power spectral densities as in previous pulsed laser excitation experiments of the nuclear transition in 229Th-doped crystals.

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Vishal Lal, Maksim V. Okhapkin, Johannes Tiedau, Niels Irwin, Valentin Petrov, Ekkehard Peik. 2025-07-23. Continuous-wave laser source at the 148 nm nuclear transition of Th-229. https://doi.org/10.1364/optica.574489

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